CN109112561A - A method of extending the stannous sulfate shelf-life - Google Patents
A method of extending the stannous sulfate shelf-life Download PDFInfo
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- CN109112561A CN109112561A CN201811115352.6A CN201811115352A CN109112561A CN 109112561 A CN109112561 A CN 109112561A CN 201811115352 A CN201811115352 A CN 201811115352A CN 109112561 A CN109112561 A CN 109112561A
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
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Abstract
A method of extending the stannous sulfate shelf-life, comprising the following steps: electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution；Cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction；Add antioxidant: sequentially adding pyrogallic acid, hydroquinone and ascorbic acid into solution after reaction, is uniformly mixed；By uniformly mixed reaction solution by the way that stannous sulfate product can be obtained after sedimentation, condensing crystallizing, separation of solid and liquid, drying.There is the danger that localised crystal is oxidized in the present invention when both having avoided Crystal Breakup, at the same also avoid surface-coating fall off product inoxidizability reduce the problem of.
Description
Technical field
The invention belongs to stannous sulfate preparation fields, and in particular to a method of extend the stannous sulfate shelf-life.
Background technique
Stannous sulfate is white or Light yellow crystals powder.It can be dissolved in water and dilute sulfuric acid, aqueous solution decomposes rapidly, and 360 DEG C
It is begun to decompose into above as basic salt, will be slow oxidation in air, become yellowish.Be mainly used for electroplating industry it is tin plating,
The heat-tinting of aluminum alloy surface, the mordant of printing and dyeing industry, hydrogen peroxide remover etc..It is used for tin plating or chemical reagent simultaneously,
Such as alloy, tinplate, steam-cylinder piston, steel wire acid electroplating, the bright tin plating etc. of electronic device.In addition, being also used to aluminium alloy
Article coatings heat-tinting, printing and dyeing industry are used as mordant, hydrogen peroxide remover etc. in organic solution.
Currently, the method for production stannous sulfate is main are as follows: be electrolysed sheet tin under sulfuric acid solvent, or straight using glass putty and sulfuric acid
It is reversed to obtain by being concentrated to get stannous sulfate product after stannous sulfate solution, but the existing technique the problem of
Be: it is tetravalent tin that when stannous sulfate product crystal is stored in air, Bivalent Tin therein is oxidizable, leads to product turbidity liter
Height, the shortened shelf life of product.
About the method for production stannous sulfate, we find following pertinent literature:
1. number of patent application: CN95205040, denomination of invention: the device of producing stannous sulfate by electrolysis, this method technique is such as
Under: the utility model is a kind of device of producing stannous sulfate by electrolysis, it has an electrolytic cell, using amberplex as electricity
The diaphragm in slot is solved, and so that electrolytic cell is formed multiple anode chambers and cathode chamber using multi-electrode, anode plate is pure tin, sulfuric acid solution
Stannous sulfate is generated in anode chamber after being electrolysed.Since anion-exchange membrane is utilized, thus eliminate spongy tin on cathode
It generates, improves the quality and quantity of product.Current efficiency and productivity effect are improved, is reduced costs, operation is easily managed,
Maintain the stabilization of product quality.But the product crystal that is disadvantageous in that of the invention in drying and storage by
To air oxidation.
2. danger blueness ion diaphragm electrolysis method prepares high-purity sulphuric acid stannous Five City University journal: natural science edition .2000,14
(1):55-59；This method prepares stannous sulfate using anion membrane electrolysis method, effectively prevents the analysis of cathode spongy tin
Out, anodic current efficiency is substantially increased.The optimum condition that this technique is had found by testing, makes Sn2+Oxidation generates Sn4+'s
Trend is minimized, and prevents anode from putting the possibility of oxygen.Anodic current density is l0mAcm-2, anode sulfuric acid concentration is
1.0mol·L-1, cathode sulfuric acid concentration is about 1.2molL-1Anode region Sn2+Content control is being lower than l00gL-1, when evaporation
Mother liquor acidity should be less than 8molL-1, the SnSO that is prepared by the technique4Product, through analyzing, purity is up to 99.9%, and items refer to
Mark reaches analysis grade standard, and efficiency is up to 99.5%.But the purity is high of this method stannous sulfate, but in the process not yet
It can be well protected stannous oxidization condition, the shelf-life of product is shorter.
3. the patent No.: denomination of invention: ZL201410846701.7 extends the method for stannous sulfate shelf life of products, the party
Method is the following steps are included: (1) is washed: by stannous sulfate solution after condensing crystallizing, separation of solid and liquid, stannous sulfate crystal second
Alcoholic solution washs 5~10min, is then centrifuged for separation, drying；(2) coating: after drying stops, stannous sulfate crystal is uniformly sprayed
The quinol solution that mass content is 0.1%~0.3% is spilt, 10~20min is stirred；Then uniformly sprinkling mass content is
0.1%~0.3% betanaphthol solution stirs 5~8min；The benzene that last uniformly sprinkling mass content is 0.05%~0.1%
And triazole solution, after 10~20min is sufficiently stirred.The method of the present invention will not only impact the quality of product, but also
Achieve the purpose that improve shelf life of products, has been increased to product 8~10 months by initial 5 months optimal shelf-lifves.The party
Method is to carry out coating processing to the product after crystallization to extend the shelf life, but product is needed through the side such as vibration screening after coating
The hardhead or other sundries occurred in formula removal product, the film that in vibration processes a part can just wrapped falls off, thus shadow
Ring effect.
Summary of the invention
Present invention aim to address above-mentioned technical problems, provide one kind and are avoided that the case where coating falls off, do not influence to produce
The method of the extension stannous sulfate shelf life of products of product purity.
To realize above-mentioned purpose, the technical solution of the present invention is as follows:
A method of extending the stannous sulfate shelf-life, comprising the following steps:
(1) electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution；
(2) cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction；
(3) plus antioxidant: pyrogallic acid, hydroquinone and anti-bad are sequentially added into solution after reaction
Hematic acid is uniformly mixed；
(4) by uniformly mixed reaction solution by the way that sulfuric acid Asia can be obtained after sedimentation, condensing crystallizing, separation of solid and liquid, drying
Tin product.
As further technical solution, the concentration of sulfuric acid solution described above is 15~25g/L.
As further technical solution, the concentration after boric acid addition described above is 1~3g/L.
As further technical solution, the concentration after pyrogallic acid addition described above is 0.1~0.2g/L, institute
Concentration after stating hydroquinone addition is 0.05~0.08g/L, and the concentration after the ascorbic acid addition is 0.02~0.05g/
L。
As further technical solution, bath voltage described above is 1.8V~2.2V, and the cell reaction time is 18
~20h.
As further technical solution, the temperature of the above drying is 60~90 DEG C, is dried to product fluidity and reaches
To primary standard.
Cell reaction in the present invention uses ion-exchange membrane electrolysis commonly used in the art, and the sedimentation mentioned, is consolidated condensing crystallizing
Liquid separation, drying are also the conventional means of this field, therefore repeat without detailed.
Compared with prior art, the invention has the benefit that
1, the present invention is utilized using sulfuric acid and refined tin as raw material, using ion-exchange membrane electrolysis technique, by adding before the reaction
Boric acid reduces the Sn occurred in electrolytic process4+；Antioxidant is added at once in stannous sulfate solution after the reaction, then settle,
Condensing crystallizing so that antioxidant is incessantly on surface, but is evenly mixed in stannous sulfate crystal, and it is broken both to have avoided crystal
Occur the danger that localised crystal is oxidized when splitting, at the same also avoid surface-coating fall off product inoxidizability reduce the problem of.
2, the present invention does not influence the purity of product.It is 4m by every tank solution is concentrated3It calculates, product quality has 450kg, anti-oxidant
Agent input amount is 0.6~1.32kg, accounts for product content less than 0.3%, obtained stannous sulfate finished product purity 99.2% or more,
Other indices meet stannous sulfate national standard, not only do not impact to the quality of product, but also have reached raising and produced
The purpose of product shelf-life, the shelf-life of product are 9~10.5 months.
Specific embodiment
Below with reference to embodiment, the present invention is described in further detail, but embodiments of the present invention are not limited to
The range that embodiment indicates.
Material involved by embodiment can be from buying on the market.
Embodiment 1:
A method of extending the stannous sulfate shelf-life, comprising the following steps:
(1) electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution, the concentration of sulfuric acid solution is 15g/L, and boric acid adds
Concentration after adding is 1g/L；
(2) cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction, electrolysis
Tank voltage is 1.8V, and the cell reaction time is 20h；
(3) plus antioxidant: pyrogallic acid, hydroquinone and anti-bad are sequentially added into solution after reaction
Hematic acid is uniformly mixed, and the concentration after pyrogallic acid addition is 0.1g/L, and the concentration after the hydroquinone addition is
0.05g/L, the concentration after the ascorbic acid addition is 0.02g/L；
(4) by uniformly mixed reaction solution by the way that sulfuric acid Asia can be obtained after sedimentation, condensing crystallizing, separation of solid and liquid, drying
Tin product.
Embodiment 2:
A method of extending the stannous sulfate shelf-life, comprising the following steps:
(1) electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution, the concentration of sulfuric acid solution is 18g/L, and boric acid adds
Concentration after adding is 1.5g/L；
(2) cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction, electrolysis
Tank voltage is 1.9V, and the cell reaction time is 20h；
(3) plus antioxidant: pyrogallic acid, hydroquinone and anti-bad are sequentially added into solution after reaction
Hematic acid is uniformly mixed, and the concentration after pyrogallic acid addition is 0.1g/L, and the concentration after the hydroquinone addition is
0.06g/L, the concentration after the ascorbic acid addition is 0.03g/L；
(4) after by uniformly mixed reaction solution by the sedimentation of same embodiment 1, condensing crystallizing, separation of solid and liquid, drying
Obtain stannous sulfate product.
Embodiment 3:
A method of extending the stannous sulfate shelf-life, comprising the following steps:
(1) electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution, the concentration of sulfuric acid solution is 20g/L, and boric acid adds
Concentration after adding is 2g/L；
(2) cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction, electrolysis
Tank voltage is 2.0V, and the cell reaction time is 19h；
(3) plus antioxidant: pyrogallic acid, hydroquinone and anti-bad are sequentially added into solution after reaction
Hematic acid is uniformly mixed, and the concentration after pyrogallic acid addition is 0.2g/L, and the concentration after the hydroquinone addition is
0.07g/L, the concentration after the ascorbic acid addition is 0.04g/L；
(4) by uniformly mixed reaction solution by the way that sulfuric acid Asia can be obtained after sedimentation, condensing crystallizing, separation of solid and liquid, drying
Tin product.
Embodiment 4:
A method of extending the stannous sulfate shelf-life, comprising the following steps:
(1) electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution, the concentration of sulfuric acid solution is 25g/L, and boric acid adds
Concentration after adding is 3g/L；
(2) cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction, electrolysis
Tank voltage is 2.2V, and the cell reaction time is 18h；
(3) plus antioxidant: pyrogallic acid, hydroquinone and anti-bad are sequentially added into solution after reaction
Hematic acid is uniformly mixed, and the concentration after pyrogallic acid addition is 0.2g/L, and the concentration after the hydroquinone addition is
0.08g/L, the concentration after the ascorbic acid addition is 0.05g/L；
(4) by uniformly mixed reaction solution by the way that sulfuric acid Asia can be obtained after sedimentation, condensing crystallizing, separation of solid and liquid, drying
Tin product.
The product index of embodiment 1-4 is as shown in table 1:
Table 1
As can be seen from Table 1, the present invention extends the method for shelf life of products, does not influence the quality of product stannous sulfate,
National standard (GB/T 23839-2009) is reached.And the shelf-life has been above 5 months before being not added with before maximum guarantors
The matter phase.
Single factor test comparative experiments
By the way that step (3) are added with following antioxidant, other steps press the operation of embodiment 3:
(A) it is not added with antioxidant；
(B) pyrogallic acid 0.31g/L is added；
(C) hydroquinone 0.31g/L is added；
(D) ascorbic acid 0.31g/L is added；
(E) betanaphthol 0.31g/L is added；
(F) benzotriazole 0.31g/L is added；
(G) hydrazine hydrate 0.31g/L is added；
(H) catechol 0.31g/L is added；
(I) pyrogallic acid 0.15g/L, hydroquinone 0.16g/L are added；
(J) pyrogallic acid 0.15g/L, ascorbic acid 0.16g/L are added；
(K) hydroquinone 0.16g/L, ascorbic acid 0.15g/L are added；
(L) hydrazine hydrate 0.15g/L, catechol 0.16g/L are added；
(M) hydroquinone 0.07g/L, betanaphthol 0.2g/L, benzotriazole 0.04g/L are added；
(N) pyrogallic acid 0.2g/L, hydroquinone 0.07g/L, ascorbic acid 0.04g/L are added.
To through above-mentioned steps, treated that stannous sulfate crystal detects, experimental result is as shown in table 2:
Table 2
| Comparative experiments | Shelf-life |
| A | 4 months |
| B | 7 months |
| C | 6 months |
| D | 6.5 months |
| E | 5.5 months |
| F | 6 months |
| G | 5 months |
| H | 6 months |
| I | 7.5 months |
| J | 7.2 months |
| K | 7.2 months |
| L | 6 months |
| M | 7.5 months |
| N | 10.5 a month |
As shown in Table 2:
(1) compared to the product for being not added with antioxidant, antioxidant of the invention makes shelf life of products extend 6.5
A month time.
(2) relative to single antioxidant, compound antioxidant of the invention makes the shelf-life of product longer.
(3) antioxidant relative to other compoundings, compound antioxidant of the invention make the shelf-life of product longer.
Above-described embodiment is only further described the purpose of the present invention, technical scheme and beneficial effects specific
A example, present invention is not limited to this.All any modification, equivalent substitution and improvement done within the scope of disclosed by the invention
Deng being all included in the scope of protection of the present invention.
Claims (5)
1. a kind of method for extending the stannous sulfate shelf-life, it is characterised in that: the following steps are included:
(1) electrolysis acid solution is prepared: boric acid is added into sulfuric acid solution；
(2) cell reaction: prepared electrolysis acid solution is put into electrolytic cell and refined tin pole plate carries out cell reaction；
(3) add antioxidant: sequentially adding pyrogallic acid, hydroquinone and Vitamin C into solution after reaction
Acid is uniformly mixed；
(4) uniformly mixed reaction solution is produced by the way that stannous sulfate can be obtained after sedimentation, condensing crystallizing, separation of solid and liquid, drying
Product.
2. a kind of method for extending the stannous sulfate shelf-life according to claim 1, it is characterised in that: the sulfuric acid solution
Concentration be 15~25g/L.
3. a kind of method for extending the stannous sulfate shelf-life according to claim 1, it is characterised in that: the boric acid addition
Concentration afterwards is 1~3g/L.
4. a kind of method for extending the stannous sulfate shelf-life according to claim 1, it is characterised in that: the coke is not eaten
Concentration after sub- acid addition is 0.1~0.2 g/L, and the concentration after the hydroquinone addition is 0.05~0.08 g/L, described
Concentration after ascorbic acid addition is 0.02~0.05 g/L.
5. a kind of method for extending the stannous sulfate shelf-life according to claim 1, it is characterised in that: the electrolyzer electric
Pressure is 1.8V~2.2V, and the cell reaction time is 18~20h.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112941574A (en) * | 2021-01-27 | 2021-06-11 | 许继电源有限公司 | Method for tin plating of external welding grounding copper conductor of cabinet |
| CN113880129A (en) * | 2021-11-17 | 2022-01-04 | 云南锡业锡化工材料有限责任公司 | Method for preparing large-particle low-dissolution-turbidity stannous sulfate |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112941574A (en) * | 2021-01-27 | 2021-06-11 | 许继电源有限公司 | Method for tin plating of external welding grounding copper conductor of cabinet |
| CN113880129A (en) * | 2021-11-17 | 2022-01-04 | 云南锡业锡化工材料有限责任公司 | Method for preparing large-particle low-dissolution-turbidity stannous sulfate |
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